1. Technical Field
The present invention relates to a printing device or the like, which is capable of having a printing material container.
2. Related Art
For a printing device that has a detecting circuit that detects the type of a printing material container (ink cartridge or the like) and detects whether or not the printing material container is attached to the printing device, and that has a circuit (printing material amount detecting circuit) that detects whether or not the amount of a printing material contained in the printing material container is equal to or larger than a predetermined amount, a technique for preventing or suppressing failures (caused by a short circuit between the detecting circuit and the printing material amount detecting circuit) of the printing material container and the printing device is described in Japanese Patent No. 4539654, for example.
A short circuit protection circuit that is included in a rechargeable secondary battery pack with a function of displaying a remaining capacity is described in JP-A-5-299123, for example.
In recent years, as a printing material container (such as an ink cartridge) capable of being attached to a printing device body, a printing material container that has a storage device for storing information (for example, a remaining amount of ink) on a printing material has been used. In addition, a technique for detecting an attachment state of the ink cartridge has been used. For example, according to Japanese Patent No. 4539654, a signal that is different from a signal to be used to detect the remaining amount of the ink is supplied to an attachment detection terminal that is not a sensor terminal to be used to detect the remaining amount of the ink, and whereby the attachment of the ink cartridge is detected.
According to Japanese Patent No. 4539654, an overvoltage detection is performed to detect whether or not a short circuit is formed between the sensor terminal and the attachment detection terminal in some cases. In the overvoltage detection, a contact detection terminal that is located adjacent to a high voltage terminal (sensor terminal) to which a voltage that is higher than a normal power supply voltage (3.3 V) is applied is connected to a circuit that detects an excessive voltage and is included in a printer, and whether or not an excessive voltage occurs in the contact detection terminal is detected, for example. When the excessive voltage is detected in the contact detection terminal, the application of the high voltage to the high voltage terminal is stopped.